just put a clutch in a r1 monday, had to drain /replace old synthetic oil as new clutch kelvar. oil just as described. more of dark gray than black. dont really know why, clutch worn badley on this bike, maybe impreginated clutch materials, oil addatives? as far as coolant in oil, never heard of a blown or leaking head gasket on a zx14, that head torques to 52 ft/lbs stock with strong studs. these are heavy built strong engines. they have had thier share of spun bearings because of the reason previousley stated. pump cover replacement makes them damn near bulletproof. got a couple of gen 1's at 200 rwhp and a gen 1 turbo at 293 on stk bottom ends. turbo guy wisely uses his power with restraint, 2 others dragraced rode hard. absolutely no problems,all 3 with billett covers installed. personally, i like these motors, will handle a lot of power reliabley.